Travelling sounds a good idea but you may find the fees/one-off registration costs for the schools less financially viable for moving around. Over here you can expect to pay a one off cost for each child to join and at least half a year's fees in advance (non refundable) but whether that is true of all, I don't know, The fees and schools themselves are pretty variable so do your homework. Asia is a particularly expat hot spot at the moment and I have heard of waiting lists for schools there.
i'm going to be a bit of a party pooper on this one - I don't think it's a good idea to keep moving around from country to country, as it will mean your kids keep having to start over making friends etc at different schools (and so will you) if you keep moving every year. i think it'll be a lot of hassle; that just when you feel settled it's time to move on again. better to relocate somewhere semi-permanently.
mts, I can see what you mean but I have got to do something and I have been thinking of moving for ages and cannot decide where to go. Maybe this way I would fall in love with a place and then stay there.
I'd misread the original idea too . Think Beetroot and mts may be right. It can take at least 9 months to find your feet and get the kids settled, especially if there is a new language involved, so it might be hard to uproot again oncce you do. Children who do, either seem to get quite blase and detached about friendships or very upset when they move or if their friends move away. If you could do an extended holiday it would give you a more instinctive feel for where might suit you all and you may decide you want to stay longer term.
btw the fees quoted are probably per annum but I've no idea how that figure converts so can't judge.
Having spent past 6 months home edding abroad my advice would be don't do it unless you have strong home support to allow you non-child time. Much as I love mine 24/7 doesn't work. From experience of others (and why we didn't choose it ourselves)apparently short term international schools can be disrupting. Only you know your children. At 3,4 and 6 I wouldn't worry myself - they'll get more from the experience than from any part time schools